FIGURE 6.

TRN2 does not inhibit apoptosis in the presence of HuR-CP1. A–C, HeLa cells were cotransfected with either a plasmid containing GFP or GFP-tagged HuR-CP1 and either CFP or CFP-TRN2. 48 h following this transfection, cells were treated with 1 μm STS for 3 h and collected or fixed. Lysates were analyzed by Western blotting using antibodies against GFP/CFP (both are recognized), cleaved caspase-3, and G3BP (loading control), a representative blot of which is shown in A. The relative levels of cleaved caspase-3 were determined and normalized to loading controls as described above, and average values are graphed in B, with error bars representing S.E. of at least three independent experiments. Alternatively, fixed cells were stained with DAPI, and 10 images were taken per condition, which allowed the percentage of cells in which nuclei were fragmented to be determined. The average percentages of cells with fragmented nuclei of three independent experiments are graphed in C, with error bars representing S.E. of three independent experiments. The asterisks indicate significant differences, with p = 0.0085 (B) and p = 0.0105 (C). NS, not statistically significant.